1 // ---------------------------------------------------------------------------
2 // PSG Sound Implementation
3 // Copyright (C) cisc 1997, 1999.
4 // ---------------------------------------------------------------------------
5 // $Id: psg.cpp,v 1.10 2002/05/15 21:38:01 cisc Exp $
6
7 #include "fmgen_headers.h"
8 #include "fmgen_misc.h"
9 #include "fmgen_psg.h"
10
11 // ---------------------------------------------------------------------------
12 // コンストラクタ・デストラクタ
13 //
PSG()14 PSG::PSG()
15 {
16 SetVolume(0);
17 MakeNoiseTable();
18 Reset();
19 mask = 0x3f;
20 }
21
~PSG()22 PSG::~PSG()
23 {
24
25 }
26
27 // ---------------------------------------------------------------------------
28 // PSG を初期化する(RESET)
29 //
Reset()30 void PSG::Reset()
31 {
32 for (int i=0; i<14; i++)
33 SetReg(i, 0);
34 SetReg(7, 0xff);
35 SetReg(14, 0xff);
36 SetReg(15, 0xff);
37 }
38
39 // ---------------------------------------------------------------------------
40 // クロック周波数の設定
41 //
SetClock(int clock,int rate)42 void PSG::SetClock(int clock, int rate)
43 {
44 tperiodbase = int((1 << toneshift ) / 4.0 * clock / rate);
45 eperiodbase = int((1 << envshift ) / 4.0 * clock / rate);
46 nperiodbase = int((1 << noiseshift) / 4.0 * clock / rate);
47
48 // 各データの更新
49 int tmp;
50 tmp = ((reg[0] + reg[1] * 256) & 0xfff);
51 speriod[0] = tmp ? tperiodbase / tmp : tperiodbase;
52 tmp = ((reg[2] + reg[3] * 256) & 0xfff);
53 speriod[1] = tmp ? tperiodbase / tmp : tperiodbase;
54 tmp = ((reg[4] + reg[5] * 256) & 0xfff);
55 speriod[2] = tmp ? tperiodbase / tmp : tperiodbase;
56 tmp = reg[6] & 0x1f;
57 nperiod = tmp ? nperiodbase / tmp / 2 : nperiodbase / 2;
58 tmp = ((reg[11] + reg[12] * 256) & 0xffff);
59 eperiod = tmp ? eperiodbase / tmp : eperiodbase * 2;
60 }
61
62 // ---------------------------------------------------------------------------
63 // ノイズテーブルを作成する
64 //
MakeNoiseTable()65 void PSG::MakeNoiseTable()
66 {
67 if (!noisetable[0])
68 {
69 int noise = 14321;
70 for (int i=0; i<noisetablesize; i++)
71 {
72 int n = 0;
73 for (int j=0; j<32; j++)
74 {
75 n = n * 2 + (noise & 1);
76 noise = (noise >> 1) | (((noise << 14) ^ (noise << 16)) & 0x10000);
77 }
78 noisetable[i] = n;
79 }
80 }
81 }
82
83 // ---------------------------------------------------------------------------
84 // 出力テーブルを作成
85 // 素直にテーブルで持ったほうが省スペース。
86 //
SetVolume(int volume)87 void PSG::SetVolume(int volume)
88 {
89 double base = 0x4000 / 3.0 * pow(10.0, volume / 40.0);
90 for (int i=31; i>=2; i--)
91 {
92 EmitTable[i] = int(base);
93 base /= 1.189207115;
94 }
95 EmitTable[1] = 0;
96 EmitTable[0] = 0;
97 MakeEnvelopTable();
98
99 SetChannelMask(~mask);
100 }
101
SetChannelMask(int c)102 void PSG::SetChannelMask(int c)
103 {
104 mask = ~c;
105 for (int i=0; i<3; i++)
106 olevel[i] = mask & (1 << i) ? EmitTable[(reg[8+i] & 15) * 2 + 1] : 0;
107 }
108
109 // ---------------------------------------------------------------------------
110 // エンベロープ波形テーブル
111 //
MakeEnvelopTable()112 void PSG::MakeEnvelopTable()
113 {
114 // 0 lo 1 up 2 down 3 hi
115 static uint8 table1[16*2] =
116 {
117 2,0, 2,0, 2,0, 2,0, 1,0, 1,0, 1,0, 1,0,
118 2,2, 2,0, 2,1, 2,3, 1,1, 1,3, 1,2, 1,0,
119 };
120 static uint8 table2[4] = { 0, 0, 31, 31 };
121 static int8 table3[4] = { 0, 1, -1, 0 };
122
123 uint* ptr = enveloptable[0];
124
125 for (int i=0; i<16*2; i++)
126 {
127 uint8 v = table2[table1[i]];
128
129 for (int j=0; j<32; j++)
130 {
131 *ptr++ = EmitTable[v];
132 v += table3[table1[i]];
133 }
134 }
135 }
136
137 // ---------------------------------------------------------------------------
138 // PSG のレジスタに値をセットする
139 // regnum レジスタの番号 (0 - 15)
140 // data セットする値
141 //
SetReg(uint regnum,uint8 data)142 void PSG::SetReg(uint regnum, uint8 data)
143 {
144 if (regnum < 0x10)
145 {
146 reg[regnum] = data;
147 switch (regnum)
148 {
149 int tmp;
150
151 case 0: // ChA Fine Tune
152 case 1: // ChA Coarse Tune
153 tmp = ((reg[0] + reg[1] * 256) & 0xfff);
154 speriod[0] = tmp ? tperiodbase / tmp : tperiodbase;
155 break;
156
157 case 2: // ChB Fine Tune
158 case 3: // ChB Coarse Tune
159 tmp = ((reg[2] + reg[3] * 256) & 0xfff);
160 speriod[1] = tmp ? tperiodbase / tmp : tperiodbase;
161 break;
162
163 case 4: // ChC Fine Tune
164 case 5: // ChC Coarse Tune
165 tmp = ((reg[4] + reg[5] * 256) & 0xfff);
166 speriod[2] = tmp ? tperiodbase / tmp : tperiodbase;
167 break;
168
169 case 6: // Noise generator control
170 data &= 0x1f;
171 nperiod = data ? nperiodbase / data : nperiodbase;
172 break;
173
174 case 8:
175 olevel[0] = mask & 1 ? EmitTable[(data & 15) * 2 + 1] : 0;
176 break;
177
178 case 9:
179 olevel[1] = mask & 2 ? EmitTable[(data & 15) * 2 + 1] : 0;
180 break;
181
182 case 10:
183 olevel[2] = mask & 4 ? EmitTable[(data & 15) * 2 + 1] : 0;
184 break;
185
186 case 11: // Envelop period
187 case 12:
188 tmp = ((reg[11] + reg[12] * 256) & 0xffff);
189 eperiod = tmp ? eperiodbase / tmp : eperiodbase * 2;
190 break;
191
192 case 13: // Envelop shape
193 ecount = 0;
194 envelop = enveloptable[data & 15];
195 break;
196 }
197 }
198 }
199
200 // ---------------------------------------------------------------------------
DataSave(struct PSGData * data)201 void PSG::DataSave(struct PSGData* data) {
202 memcpy(data->reg, reg, 16);
203 memcpy(data->olevel, olevel, sizeof(uint) * 6);
204 memcpy(data->scount, scount, sizeof(uint32) * 3);
205 memcpy(data->speriod, speriod, sizeof(uint32) * 3);
206 data->ecount = ecount;
207 data->eperiod = eperiod;
208 data->ncount = ncount;
209 data->nperiod = nperiod;
210 data->tperiodbase = tperiodbase;
211 data->eperiodbase = eperiodbase;
212 data->nperiodbase = nperiodbase;
213 data->volume = volume;
214 data->mask = mask;
215 }
216
217 // ---------------------------------------------------------------------------
DataLoad(struct PSGData * data)218 void PSG::DataLoad(struct PSGData* data) {
219 memcpy(reg, data->reg, 16);
220 memcpy(olevel, data->olevel, sizeof(uint) * 6);
221 memcpy(scount, data->scount, sizeof(uint32) * 3);
222 memcpy(speriod, data->speriod, sizeof(uint32) * 3);
223 ecount = data->ecount;
224 eperiod = data->eperiod;
225 ncount = data->ncount;
226 nperiod = data->nperiod;
227 tperiodbase = data->tperiodbase;
228 eperiodbase = data->eperiodbase;
229 nperiodbase = data->nperiodbase;
230 volume = data->volume;
231 mask = data->mask;
232 }
233
234 // ---------------------------------------------------------------------------
235 //
236 //
StoreSample(Sample & dest,int32 data)237 inline void PSG::StoreSample(Sample& dest, int32 data)
238 {
239 if (sizeof(Sample) == 2)
240 dest = (Sample) Limit(dest + data, 0x7fff, -0x8000);
241 else
242 dest += data;
243 }
244
245 // ---------------------------------------------------------------------------
246 // PCM データを吐き出す(2ch)
247 // dest PCM データを展開するポインタ
248 // nsamples 展開する PCM のサンプル数
249 //
Mix(Sample * dest,int nsamples)250 void PSG::Mix(Sample* dest, int nsamples)
251 {
252 uint8 chenable[3], nenable[3];
253 uint8 r7 = ~reg[7];
254
255 if ((r7 & 0x3f) | ((reg[8] | reg[9] | reg[10]) & 0x1f))
256 {
257 chenable[0] = (r7 & 0x01) && (speriod[0] <= (1 << toneshift));
258 chenable[1] = (r7 & 0x02) && (speriod[1] <= (1 << toneshift));
259 chenable[2] = (r7 & 0x04) && (speriod[2] <= (1 << toneshift));
260 nenable[0] = (r7 >> 3) & 1;
261 nenable[1] = (r7 >> 4) & 1;
262 nenable[2] = (r7 >> 5) & 1;
263
264 int noise, sample;
265 uint env;
266 uint* p1 = ((mask & 1) && (reg[ 8] & 0x10)) ? &env : &olevel[0];
267 uint* p2 = ((mask & 2) && (reg[ 9] & 0x10)) ? &env : &olevel[1];
268 uint* p3 = ((mask & 4) && (reg[10] & 0x10)) ? &env : &olevel[2];
269
270 #define SCOUNT(ch) (scount[ch] >> (toneshift+oversampling))
271
272 if (p1 != &env && p2 != &env && p3 != &env)
273 {
274 // エンベロープ無し
275 if ((r7 & 0x38) == 0)
276 {
277 // ノイズ無し
278 for (int i=0; i<nsamples; i++)
279 {
280 sample = 0;
281 for (int j=0; j < (1 << oversampling); j++)
282 {
283 int x, y, z;
284 x = (SCOUNT(0) & chenable[0]) - 1;
285 sample += (olevel[0] + x) ^ x;
286 scount[0] += speriod[0];
287 y = (SCOUNT(1) & chenable[1]) - 1;
288 sample += (olevel[1] + y) ^ y;
289 scount[1] += speriod[1];
290 z = (SCOUNT(2) & chenable[2]) - 1;
291 sample += (olevel[2] + z) ^ z;
292 scount[2] += speriod[2];
293 }
294 sample /= (1 << oversampling);
295 StoreSample(dest[0], sample);
296 StoreSample(dest[1], sample);
297 dest += 2;
298 }
299 }
300 else
301 {
302 // ノイズ有り
303 for (int i=0; i<nsamples; i++)
304 {
305 sample = 0;
306 for (int j=0; j < (1 << oversampling); j++)
307 {
308 #ifdef _M_IX86
309 noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
310 >> (ncount >> (noiseshift+oversampling+1));
311 #else
312 noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
313 >> (ncount >> (noiseshift+oversampling+1) & 31);
314 #endif
315 ncount += nperiod;
316
317 int x, y, z;
318 x = ((SCOUNT(0) & chenable[0]) | (nenable[0] & noise)) - 1; // 0 or -1
319 sample += (olevel[0] + x) ^ x;
320 scount[0] += speriod[0];
321 y = ((SCOUNT(1) & chenable[1]) | (nenable[1] & noise)) - 1;
322 sample += (olevel[1] + y) ^ y;
323 scount[1] += speriod[1];
324 z = ((SCOUNT(2) & chenable[2]) | (nenable[2] & noise)) - 1;
325 sample += (olevel[2] + z) ^ z;
326 scount[2] += speriod[2];
327 }
328 sample /= (1 << oversampling);
329 StoreSample(dest[0], sample);
330 StoreSample(dest[1], sample);
331 dest += 2;
332 }
333 }
334
335 // エンベロープの計算をさぼった帳尻あわせ
336 ecount = (ecount >> 8) + (eperiod >> (8-oversampling)) * nsamples;
337 if (ecount >= (1 << (envshift+6+oversampling-8)))
338 {
339 if ((reg[0x0d] & 0x0b) != 0x0a)
340 ecount |= (1 << (envshift+5+oversampling-8));
341 ecount &= (1 << (envshift+6+oversampling-8)) - 1;
342 }
343 ecount <<= 8;
344 }
345 else
346 {
347 // エンベロープあり
348 for (int i=0; i<nsamples; i++)
349 {
350 sample = 0;
351 for (int j=0; j < (1 << oversampling); j++)
352 {
353 env = envelop[ecount >> (envshift+oversampling)];
354 ecount += eperiod;
355 if (ecount >= (1 << (envshift+6+oversampling)))
356 {
357 if ((reg[0x0d] & 0x0b) != 0x0a)
358 ecount |= (1 << (envshift+5+oversampling));
359 ecount &= (1 << (envshift+6+oversampling)) - 1;
360 }
361 #ifdef _M_IX86
362 noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
363 >> (ncount >> (noiseshift+oversampling+1));
364 #else
365 noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
366 >> (ncount >> (noiseshift+oversampling+1) & 31);
367 #endif
368 ncount += nperiod;
369
370 int x, y, z;
371 x = ((SCOUNT(0) & chenable[0]) | (nenable[0] & noise)) - 1; // 0 or -1
372 sample += (*p1 + x) ^ x;
373 scount[0] += speriod[0];
374 y = ((SCOUNT(1) & chenable[1]) | (nenable[1] & noise)) - 1;
375 sample += (*p2 + y) ^ y;
376 scount[1] += speriod[1];
377 z = ((SCOUNT(2) & chenable[2]) | (nenable[2] & noise)) - 1;
378 sample += (*p3 + z) ^ z;
379 scount[2] += speriod[2];
380 }
381 sample /= (1 << oversampling);
382 StoreSample(dest[0], sample);
383 StoreSample(dest[1], sample);
384 dest += 2;
385 }
386 }
387 }
388 }
389
390 // ---------------------------------------------------------------------------
391 // テーブル
392 //
393 uint PSG::noisetable[noisetablesize] = { 0, };
394 int PSG::EmitTable[0x20] = { -1, };
395 uint PSG::enveloptable[16][64] = { {0, } };
396